1use std::{borrow::Cow, sync::Arc};
2
3use ::util::ResultExt;
4use anyhow::Result;
5use collections::HashMap;
6use itertools::Itertools;
7use parking_lot::{RwLock, RwLockUpgradableReadGuard};
8use windows::{
9 Win32::{
10 Foundation::*,
11 Globalization::GetUserDefaultLocaleName,
12 Graphics::{
13 Direct3D::D3D_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP,
14 Direct3D11::*,
15 DirectWrite::*,
16 Dxgi::Common::*,
17 Gdi::{IsRectEmpty, LOGFONTW},
18 Imaging::*,
19 },
20 System::SystemServices::LOCALE_NAME_MAX_LENGTH,
21 UI::WindowsAndMessaging::*,
22 },
23 core::*,
24};
25use windows_numerics::Vector2;
26
27use crate::*;
28
29#[derive(Debug)]
30struct FontInfo {
31 font_family: String,
32 font_face: IDWriteFontFace3,
33 features: IDWriteTypography,
34 fallbacks: Option<IDWriteFontFallback>,
35 is_system_font: bool,
36}
37
38pub(crate) struct DirectWriteTextSystem(RwLock<DirectWriteState>);
39
40struct DirectWriteComponent {
41 locale: String,
42 factory: IDWriteFactory5,
43 bitmap_factory: AgileReference<IWICImagingFactory>,
44 in_memory_loader: IDWriteInMemoryFontFileLoader,
45 builder: IDWriteFontSetBuilder1,
46 text_renderer: Arc<TextRendererWrapper>,
47
48 render_params: IDWriteRenderingParams3,
49 gpu_state: GPUState,
50}
51
52struct GPUState {
53 device: ID3D11Device,
54 device_context: ID3D11DeviceContext,
55 sampler: [Option<ID3D11SamplerState>; 1],
56 blend_state: ID3D11BlendState,
57 vertex_shader: ID3D11VertexShader,
58 pixel_shader: ID3D11PixelShader,
59}
60
61struct DirectWriteState {
62 components: DirectWriteComponent,
63 system_ui_font_name: SharedString,
64 system_font_collection: IDWriteFontCollection1,
65 custom_font_collection: IDWriteFontCollection1,
66 fonts: Vec<FontInfo>,
67 font_selections: HashMap<Font, FontId>,
68 font_id_by_identifier: HashMap<FontIdentifier, FontId>,
69}
70
71#[derive(Debug, Clone, Hash, PartialEq, Eq)]
72struct FontIdentifier {
73 postscript_name: String,
74 weight: i32,
75 style: i32,
76}
77
78impl DirectWriteComponent {
79 pub fn new(bitmap_factory: &IWICImagingFactory, gpu_context: &DirectXDevices) -> Result<Self> {
80 // todo: ideally this would not be a large unsafe block but smaller isolated ones for easier auditing
81 unsafe {
82 let factory: IDWriteFactory5 = DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED)?;
83 let bitmap_factory = AgileReference::new(bitmap_factory)?;
84 // The `IDWriteInMemoryFontFileLoader` here is supported starting from
85 // Windows 10 Creators Update, which consequently requires the entire
86 // `DirectWriteTextSystem` to run on `win10 1703`+.
87 let in_memory_loader = factory.CreateInMemoryFontFileLoader()?;
88 factory.RegisterFontFileLoader(&in_memory_loader)?;
89 let builder = factory.CreateFontSetBuilder()?;
90 let mut locale_vec = vec![0u16; LOCALE_NAME_MAX_LENGTH as usize];
91 GetUserDefaultLocaleName(&mut locale_vec);
92 let locale = String::from_utf16_lossy(&locale_vec);
93 let text_renderer = Arc::new(TextRendererWrapper::new(&locale));
94
95 let render_params = {
96 let default_params: IDWriteRenderingParams3 =
97 factory.CreateRenderingParams()?.cast()?;
98 let gamma = default_params.GetGamma();
99 let enhanced_contrast = default_params.GetEnhancedContrast();
100 let gray_contrast = default_params.GetGrayscaleEnhancedContrast();
101 let cleartype_level = default_params.GetClearTypeLevel();
102 let grid_fit_mode = default_params.GetGridFitMode();
103
104 factory.CreateCustomRenderingParams(
105 gamma,
106 enhanced_contrast,
107 gray_contrast,
108 cleartype_level,
109 DWRITE_PIXEL_GEOMETRY_RGB,
110 DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC,
111 grid_fit_mode,
112 )?
113 };
114
115 let gpu_state = GPUState::new(gpu_context)?;
116
117 Ok(DirectWriteComponent {
118 locale,
119 factory,
120 bitmap_factory,
121 in_memory_loader,
122 builder,
123 text_renderer,
124 render_params,
125 gpu_state,
126 })
127 }
128 }
129}
130
131impl GPUState {
132 fn new(gpu_context: &DirectXDevices) -> Result<Self> {
133 let device = gpu_context.device.clone();
134 let device_context = gpu_context.device_context.clone();
135
136 let blend_state = {
137 let mut blend_state = None;
138 let desc = D3D11_BLEND_DESC {
139 AlphaToCoverageEnable: false.into(),
140 IndependentBlendEnable: false.into(),
141 RenderTarget: [
142 D3D11_RENDER_TARGET_BLEND_DESC {
143 BlendEnable: true.into(),
144 SrcBlend: D3D11_BLEND_SRC_ALPHA,
145 DestBlend: D3D11_BLEND_INV_SRC_ALPHA,
146 BlendOp: D3D11_BLEND_OP_ADD,
147 SrcBlendAlpha: D3D11_BLEND_SRC_ALPHA,
148 DestBlendAlpha: D3D11_BLEND_INV_SRC_ALPHA,
149 BlendOpAlpha: D3D11_BLEND_OP_ADD,
150 RenderTargetWriteMask: D3D11_COLOR_WRITE_ENABLE_ALL.0 as u8,
151 },
152 Default::default(),
153 Default::default(),
154 Default::default(),
155 Default::default(),
156 Default::default(),
157 Default::default(),
158 Default::default(),
159 ],
160 };
161 unsafe { device.CreateBlendState(&desc, Some(&mut blend_state)) }?;
162 blend_state.unwrap()
163 };
164
165 let sampler = {
166 let mut sampler = None;
167 let desc = D3D11_SAMPLER_DESC {
168 Filter: D3D11_FILTER_MIN_MAG_MIP_POINT,
169 AddressU: D3D11_TEXTURE_ADDRESS_BORDER,
170 AddressV: D3D11_TEXTURE_ADDRESS_BORDER,
171 AddressW: D3D11_TEXTURE_ADDRESS_BORDER,
172 MipLODBias: 0.0,
173 MaxAnisotropy: 1,
174 ComparisonFunc: D3D11_COMPARISON_ALWAYS,
175 BorderColor: [0.0, 0.0, 0.0, 0.0],
176 MinLOD: 0.0,
177 MaxLOD: 0.0,
178 };
179 unsafe { device.CreateSamplerState(&desc, Some(&mut sampler)) }?;
180 [sampler]
181 };
182
183 let vertex_shader = {
184 let source = shader_resources::RawShaderBytes::new(
185 shader_resources::ShaderModule::EmojiRasterization,
186 shader_resources::ShaderTarget::Vertex,
187 )?;
188 let mut shader = None;
189 unsafe { device.CreateVertexShader(source.as_bytes(), None, Some(&mut shader)) }?;
190 shader.unwrap()
191 };
192
193 let pixel_shader = {
194 let source = shader_resources::RawShaderBytes::new(
195 shader_resources::ShaderModule::EmojiRasterization,
196 shader_resources::ShaderTarget::Fragment,
197 )?;
198 let mut shader = None;
199 unsafe { device.CreatePixelShader(source.as_bytes(), None, Some(&mut shader)) }?;
200 shader.unwrap()
201 };
202
203 Ok(Self {
204 device,
205 device_context,
206 sampler,
207 blend_state,
208 vertex_shader,
209 pixel_shader,
210 })
211 }
212}
213
214impl DirectWriteTextSystem {
215 pub(crate) fn new(
216 gpu_context: &DirectXDevices,
217 bitmap_factory: &IWICImagingFactory,
218 ) -> Result<Self> {
219 let components = DirectWriteComponent::new(bitmap_factory, gpu_context)?;
220 let system_font_collection = unsafe {
221 let mut result = std::mem::zeroed();
222 components
223 .factory
224 .GetSystemFontCollection(false, &mut result, true)?;
225 result.unwrap()
226 };
227 let custom_font_set = unsafe { components.builder.CreateFontSet()? };
228 let custom_font_collection = unsafe {
229 components
230 .factory
231 .CreateFontCollectionFromFontSet(&custom_font_set)?
232 };
233 let system_ui_font_name = get_system_ui_font_name();
234
235 Ok(Self(RwLock::new(DirectWriteState {
236 components,
237 system_ui_font_name,
238 system_font_collection,
239 custom_font_collection,
240 fonts: Vec::new(),
241 font_selections: HashMap::default(),
242 font_id_by_identifier: HashMap::default(),
243 })))
244 }
245}
246
247impl PlatformTextSystem for DirectWriteTextSystem {
248 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
249 self.0.write().add_fonts(fonts)
250 }
251
252 fn all_font_names(&self) -> Vec<String> {
253 self.0.read().all_font_names()
254 }
255
256 fn font_id(&self, font: &Font) -> Result<FontId> {
257 let lock = self.0.upgradable_read();
258 if let Some(font_id) = lock.font_selections.get(font) {
259 Ok(*font_id)
260 } else {
261 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
262 let font_id = lock.select_font(font);
263 lock.font_selections.insert(font.clone(), font_id);
264 Ok(font_id)
265 }
266 }
267
268 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
269 self.0.read().font_metrics(font_id)
270 }
271
272 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
273 self.0.read().get_typographic_bounds(font_id, glyph_id)
274 }
275
276 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result<Size<f32>> {
277 self.0.read().get_advance(font_id, glyph_id)
278 }
279
280 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
281 self.0.read().glyph_for_char(font_id, ch)
282 }
283
284 fn glyph_raster_bounds(
285 &self,
286 params: &RenderGlyphParams,
287 ) -> anyhow::Result<Bounds<DevicePixels>> {
288 self.0.read().raster_bounds(params)
289 }
290
291 fn rasterize_glyph(
292 &self,
293 params: &RenderGlyphParams,
294 raster_bounds: Bounds<DevicePixels>,
295 ) -> anyhow::Result<(Size<DevicePixels>, Vec<u8>)> {
296 self.0.read().rasterize_glyph(params, raster_bounds)
297 }
298
299 fn layout_line(&self, text: &str, font_size: Pixels, runs: &[FontRun]) -> LineLayout {
300 self.0
301 .write()
302 .layout_line(text, font_size, runs)
303 .log_err()
304 .unwrap_or(LineLayout {
305 font_size,
306 ..Default::default()
307 })
308 }
309}
310
311impl DirectWriteState {
312 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
313 for font_data in fonts {
314 match font_data {
315 Cow::Borrowed(data) => unsafe {
316 let font_file = self
317 .components
318 .in_memory_loader
319 .CreateInMemoryFontFileReference(
320 &self.components.factory,
321 data.as_ptr() as _,
322 data.len() as _,
323 None,
324 )?;
325 self.components.builder.AddFontFile(&font_file)?;
326 },
327 Cow::Owned(data) => unsafe {
328 let font_file = self
329 .components
330 .in_memory_loader
331 .CreateInMemoryFontFileReference(
332 &self.components.factory,
333 data.as_ptr() as _,
334 data.len() as _,
335 None,
336 )?;
337 self.components.builder.AddFontFile(&font_file)?;
338 },
339 }
340 }
341 let set = unsafe { self.components.builder.CreateFontSet()? };
342 let collection = unsafe {
343 self.components
344 .factory
345 .CreateFontCollectionFromFontSet(&set)?
346 };
347 self.custom_font_collection = collection;
348
349 Ok(())
350 }
351
352 fn generate_font_fallbacks(
353 &self,
354 fallbacks: &FontFallbacks,
355 ) -> Result<Option<IDWriteFontFallback>> {
356 if fallbacks.fallback_list().is_empty() {
357 return Ok(None);
358 }
359 unsafe {
360 let builder = self.components.factory.CreateFontFallbackBuilder()?;
361 let font_set = &self.system_font_collection.GetFontSet()?;
362 for family_name in fallbacks.fallback_list() {
363 let Some(fonts) = font_set
364 .GetMatchingFonts(
365 &HSTRING::from(family_name),
366 DWRITE_FONT_WEIGHT_NORMAL,
367 DWRITE_FONT_STRETCH_NORMAL,
368 DWRITE_FONT_STYLE_NORMAL,
369 )
370 .log_err()
371 else {
372 continue;
373 };
374 if fonts.GetFontCount() == 0 {
375 log::error!("No matching font found for {}", family_name);
376 continue;
377 }
378 let font = fonts.GetFontFaceReference(0)?.CreateFontFace()?;
379 let mut count = 0;
380 font.GetUnicodeRanges(None, &mut count).ok();
381 if count == 0 {
382 continue;
383 }
384 let mut unicode_ranges = vec![DWRITE_UNICODE_RANGE::default(); count as usize];
385 let Some(_) = font
386 .GetUnicodeRanges(Some(&mut unicode_ranges), &mut count)
387 .log_err()
388 else {
389 continue;
390 };
391 let target_family_name = HSTRING::from(family_name);
392 builder.AddMapping(
393 &unicode_ranges,
394 &[target_family_name.as_ptr()],
395 None,
396 None,
397 None,
398 1.0,
399 )?;
400 }
401 let system_fallbacks = self.components.factory.GetSystemFontFallback()?;
402 builder.AddMappings(&system_fallbacks)?;
403 Ok(Some(builder.CreateFontFallback()?))
404 }
405 }
406
407 unsafe fn generate_font_features(
408 &self,
409 font_features: &FontFeatures,
410 ) -> Result<IDWriteTypography> {
411 let direct_write_features = unsafe { self.components.factory.CreateTypography()? };
412 apply_font_features(&direct_write_features, font_features)?;
413 Ok(direct_write_features)
414 }
415
416 unsafe fn get_font_id_from_font_collection(
417 &mut self,
418 family_name: &str,
419 font_weight: FontWeight,
420 font_style: FontStyle,
421 font_features: &FontFeatures,
422 font_fallbacks: Option<&FontFallbacks>,
423 is_system_font: bool,
424 ) -> Option<FontId> {
425 let collection = if is_system_font {
426 &self.system_font_collection
427 } else {
428 &self.custom_font_collection
429 };
430 let fontset = unsafe { collection.GetFontSet().log_err()? };
431 let font = unsafe {
432 fontset
433 .GetMatchingFonts(
434 &HSTRING::from(family_name),
435 font_weight.into(),
436 DWRITE_FONT_STRETCH_NORMAL,
437 font_style.into(),
438 )
439 .log_err()?
440 };
441 let total_number = unsafe { font.GetFontCount() };
442 for index in 0..total_number {
443 let Some(font_face_ref) = (unsafe { font.GetFontFaceReference(index).log_err() })
444 else {
445 continue;
446 };
447 let Some(font_face) = (unsafe { font_face_ref.CreateFontFace().log_err() }) else {
448 continue;
449 };
450 let Some(identifier) = get_font_identifier(&font_face, &self.components.locale) else {
451 continue;
452 };
453 let Some(direct_write_features) =
454 (unsafe { self.generate_font_features(font_features).log_err() })
455 else {
456 continue;
457 };
458 let fallbacks = font_fallbacks
459 .and_then(|fallbacks| self.generate_font_fallbacks(fallbacks).log_err().flatten());
460 let font_info = FontInfo {
461 font_family: family_name.to_owned(),
462 font_face,
463 features: direct_write_features,
464 fallbacks,
465 is_system_font,
466 };
467 let font_id = FontId(self.fonts.len());
468 self.fonts.push(font_info);
469 self.font_id_by_identifier.insert(identifier, font_id);
470 return Some(font_id);
471 }
472 None
473 }
474
475 unsafe fn update_system_font_collection(&mut self) {
476 let mut collection = unsafe { std::mem::zeroed() };
477 if unsafe {
478 self.components
479 .factory
480 .GetSystemFontCollection(false, &mut collection, true)
481 .log_err()
482 .is_some()
483 } {
484 self.system_font_collection = collection.unwrap();
485 }
486 }
487
488 fn select_font(&mut self, target_font: &Font) -> FontId {
489 unsafe {
490 if target_font.family == ".SystemUIFont" {
491 let family = self.system_ui_font_name.clone();
492 self.find_font_id(
493 family.as_ref(),
494 target_font.weight,
495 target_font.style,
496 &target_font.features,
497 target_font.fallbacks.as_ref(),
498 )
499 .unwrap()
500 } else {
501 self.find_font_id(
502 target_font.family.as_ref(),
503 target_font.weight,
504 target_font.style,
505 &target_font.features,
506 target_font.fallbacks.as_ref(),
507 )
508 .unwrap_or_else(|| {
509 #[cfg(any(test, feature = "test-support"))]
510 {
511 panic!("ERROR: {} font not found!", target_font.family);
512 }
513 #[cfg(not(any(test, feature = "test-support")))]
514 {
515 let family = self.system_ui_font_name.clone();
516 log::error!("{} not found, use {} instead.", target_font.family, family);
517 self.get_font_id_from_font_collection(
518 family.as_ref(),
519 target_font.weight,
520 target_font.style,
521 &target_font.features,
522 target_font.fallbacks.as_ref(),
523 true,
524 )
525 .unwrap()
526 }
527 })
528 }
529 }
530 }
531
532 unsafe fn find_font_id(
533 &mut self,
534 family_name: &str,
535 weight: FontWeight,
536 style: FontStyle,
537 features: &FontFeatures,
538 fallbacks: Option<&FontFallbacks>,
539 ) -> Option<FontId> {
540 // try to find target font in custom font collection first
541 unsafe {
542 self.get_font_id_from_font_collection(
543 family_name,
544 weight,
545 style,
546 features,
547 fallbacks,
548 false,
549 )
550 .or_else(|| {
551 self.get_font_id_from_font_collection(
552 family_name,
553 weight,
554 style,
555 features,
556 fallbacks,
557 true,
558 )
559 })
560 .or_else(|| {
561 self.update_system_font_collection();
562 self.get_font_id_from_font_collection(
563 family_name,
564 weight,
565 style,
566 features,
567 fallbacks,
568 true,
569 )
570 })
571 }
572 }
573
574 fn layout_line(
575 &mut self,
576 text: &str,
577 font_size: Pixels,
578 font_runs: &[FontRun],
579 ) -> Result<LineLayout> {
580 if font_runs.is_empty() {
581 return Ok(LineLayout {
582 font_size,
583 ..Default::default()
584 });
585 }
586 unsafe {
587 let text_renderer = self.components.text_renderer.clone();
588 let text_wide = text.encode_utf16().collect_vec();
589
590 let mut utf8_offset = 0usize;
591 let mut utf16_offset = 0u32;
592 let text_layout = {
593 let first_run = &font_runs[0];
594 let font_info = &self.fonts[first_run.font_id.0];
595 let collection = if font_info.is_system_font {
596 &self.system_font_collection
597 } else {
598 &self.custom_font_collection
599 };
600 let format: IDWriteTextFormat1 = self
601 .components
602 .factory
603 .CreateTextFormat(
604 &HSTRING::from(&font_info.font_family),
605 collection,
606 font_info.font_face.GetWeight(),
607 font_info.font_face.GetStyle(),
608 DWRITE_FONT_STRETCH_NORMAL,
609 font_size.0,
610 &HSTRING::from(&self.components.locale),
611 )?
612 .cast()?;
613 if let Some(ref fallbacks) = font_info.fallbacks {
614 format.SetFontFallback(fallbacks)?;
615 }
616
617 let layout = self.components.factory.CreateTextLayout(
618 &text_wide,
619 &format,
620 f32::INFINITY,
621 f32::INFINITY,
622 )?;
623 let current_text = &text[utf8_offset..(utf8_offset + first_run.len)];
624 utf8_offset += first_run.len;
625 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
626 let text_range = DWRITE_TEXT_RANGE {
627 startPosition: utf16_offset,
628 length: current_text_utf16_length,
629 };
630 layout.SetTypography(&font_info.features, text_range)?;
631 utf16_offset += current_text_utf16_length;
632
633 layout
634 };
635
636 let mut first_run = true;
637 let mut ascent = Pixels::default();
638 let mut descent = Pixels::default();
639 for run in font_runs {
640 if first_run {
641 first_run = false;
642 let mut metrics = vec![DWRITE_LINE_METRICS::default(); 4];
643 let mut line_count = 0u32;
644 text_layout.GetLineMetrics(Some(&mut metrics), &mut line_count as _)?;
645 ascent = px(metrics[0].baseline);
646 descent = px(metrics[0].height - metrics[0].baseline);
647 continue;
648 }
649 let font_info = &self.fonts[run.font_id.0];
650 let current_text = &text[utf8_offset..(utf8_offset + run.len)];
651 utf8_offset += run.len;
652 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
653
654 let collection = if font_info.is_system_font {
655 &self.system_font_collection
656 } else {
657 &self.custom_font_collection
658 };
659 let text_range = DWRITE_TEXT_RANGE {
660 startPosition: utf16_offset,
661 length: current_text_utf16_length,
662 };
663 utf16_offset += current_text_utf16_length;
664 text_layout.SetFontCollection(collection, text_range)?;
665 text_layout
666 .SetFontFamilyName(&HSTRING::from(&font_info.font_family), text_range)?;
667 text_layout.SetFontSize(font_size.0, text_range)?;
668 text_layout.SetFontStyle(font_info.font_face.GetStyle(), text_range)?;
669 text_layout.SetFontWeight(font_info.font_face.GetWeight(), text_range)?;
670 text_layout.SetTypography(&font_info.features, text_range)?;
671 }
672
673 let mut runs = Vec::new();
674 let renderer_context = RendererContext {
675 text_system: self,
676 index_converter: StringIndexConverter::new(text),
677 runs: &mut runs,
678 width: 0.0,
679 };
680 text_layout.Draw(
681 Some(&renderer_context as *const _ as _),
682 &text_renderer.0,
683 0.0,
684 0.0,
685 )?;
686 let width = px(renderer_context.width);
687
688 Ok(LineLayout {
689 font_size,
690 width,
691 ascent,
692 descent,
693 runs,
694 len: text.len(),
695 })
696 }
697 }
698
699 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
700 unsafe {
701 let font_info = &self.fonts[font_id.0];
702 let mut metrics = std::mem::zeroed();
703 font_info.font_face.GetMetrics(&mut metrics);
704
705 FontMetrics {
706 units_per_em: metrics.Base.designUnitsPerEm as _,
707 ascent: metrics.Base.ascent as _,
708 descent: -(metrics.Base.descent as f32),
709 line_gap: metrics.Base.lineGap as _,
710 underline_position: metrics.Base.underlinePosition as _,
711 underline_thickness: metrics.Base.underlineThickness as _,
712 cap_height: metrics.Base.capHeight as _,
713 x_height: metrics.Base.xHeight as _,
714 bounding_box: Bounds {
715 origin: Point {
716 x: metrics.glyphBoxLeft as _,
717 y: metrics.glyphBoxBottom as _,
718 },
719 size: Size {
720 width: (metrics.glyphBoxRight - metrics.glyphBoxLeft) as _,
721 height: (metrics.glyphBoxTop - metrics.glyphBoxBottom) as _,
722 },
723 },
724 }
725 }
726 }
727
728 fn create_glyph_run_analysis(
729 &self,
730 params: &RenderGlyphParams,
731 ) -> Result<IDWriteGlyphRunAnalysis> {
732 let font = &self.fonts[params.font_id.0];
733 let glyph_id = [params.glyph_id.0 as u16];
734 let advance = [0.0];
735 let offset = [DWRITE_GLYPH_OFFSET::default()];
736 let glyph_run = DWRITE_GLYPH_RUN {
737 fontFace: unsafe { std::mem::transmute_copy(&font.font_face) },
738 fontEmSize: params.font_size.0,
739 glyphCount: 1,
740 glyphIndices: glyph_id.as_ptr(),
741 glyphAdvances: advance.as_ptr(),
742 glyphOffsets: offset.as_ptr(),
743 isSideways: BOOL(0),
744 bidiLevel: 0,
745 };
746 let transform = DWRITE_MATRIX {
747 m11: params.scale_factor,
748 m12: 0.0,
749 m21: 0.0,
750 m22: params.scale_factor,
751 dx: 0.0,
752 dy: 0.0,
753 };
754 let subpixel_shift = params
755 .subpixel_variant
756 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
757 let baseline_origin_x = subpixel_shift.x / params.scale_factor;
758 let baseline_origin_y = subpixel_shift.y / params.scale_factor;
759
760 let mut rendering_mode = DWRITE_RENDERING_MODE1::default();
761 let mut grid_fit_mode = DWRITE_GRID_FIT_MODE::default();
762 unsafe {
763 font.font_face.GetRecommendedRenderingMode(
764 params.font_size.0,
765 // The dpi here seems that it has the same effect with `Some(&transform)`
766 1.0,
767 1.0,
768 Some(&transform),
769 false,
770 DWRITE_OUTLINE_THRESHOLD_ANTIALIASED,
771 DWRITE_MEASURING_MODE_NATURAL,
772 &self.components.render_params,
773 &mut rendering_mode,
774 &mut grid_fit_mode,
775 )?;
776 }
777
778 let glyph_analysis = unsafe {
779 self.components.factory.CreateGlyphRunAnalysis(
780 &glyph_run,
781 Some(&transform),
782 rendering_mode,
783 DWRITE_MEASURING_MODE_NATURAL,
784 grid_fit_mode,
785 DWRITE_TEXT_ANTIALIAS_MODE_CLEARTYPE,
786 baseline_origin_x,
787 baseline_origin_y,
788 )
789 }?;
790 Ok(glyph_analysis)
791 }
792
793 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
794 let glyph_analysis = self.create_glyph_run_analysis(params)?;
795
796 if params.is_emoji {
797 let bounds =
798 unsafe { glyph_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1)? };
799 // If it's empty, retry with grayscale AA.
800 if !unsafe { IsRectEmpty(&bounds) }.as_bool() {
801 return Ok(Bounds {
802 origin: point((bounds.left as i32).into(), (bounds.top as i32).into()),
803 size: size(
804 (bounds.right - bounds.left).into(),
805 (bounds.bottom - bounds.top).into(),
806 ),
807 });
808 }
809 }
810
811 let bounds = unsafe { glyph_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1)? };
812
813 if bounds.right < bounds.left {
814 Ok(Bounds {
815 origin: point(0.into(), 0.into()),
816 size: size(0.into(), 0.into()),
817 })
818 } else {
819 Ok(Bounds {
820 origin: point((bounds.left as i32).into(), (bounds.top as i32).into()),
821 size: size(
822 (bounds.right - bounds.left).into(),
823 (bounds.bottom - bounds.top).into(),
824 ),
825 })
826 }
827 }
828
829 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
830 let font_info = &self.fonts[font_id.0];
831 let codepoints = [ch as u32];
832 let mut glyph_indices = vec![0u16; 1];
833 unsafe {
834 font_info
835 .font_face
836 .GetGlyphIndices(codepoints.as_ptr(), 1, glyph_indices.as_mut_ptr())
837 .log_err()
838 }
839 .map(|_| GlyphId(glyph_indices[0] as u32))
840 }
841
842 fn rasterize_glyph(
843 &self,
844 params: &RenderGlyphParams,
845 glyph_bounds: Bounds<DevicePixels>,
846 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
847 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
848 anyhow::bail!("glyph bounds are empty");
849 }
850
851 let bitmap_data = if params.is_emoji {
852 if let Ok(color) = self.rasterize_color(¶ms, glyph_bounds) {
853 color
854 } else {
855 let monochrome = self.rasterize_monochrome(params, glyph_bounds)?;
856 monochrome
857 .into_iter()
858 .flat_map(|pixel| [0, 0, 0, pixel])
859 .collect::<Vec<_>>()
860 }
861 } else {
862 self.rasterize_monochrome(params, glyph_bounds)?
863 };
864
865 Ok((glyph_bounds.size, bitmap_data))
866 }
867
868 fn rasterize_monochrome(
869 &self,
870 params: &RenderGlyphParams,
871 glyph_bounds: Bounds<DevicePixels>,
872 ) -> Result<Vec<u8>> {
873 let mut bitmap_data =
874 vec![0u8; glyph_bounds.size.width.0 as usize * glyph_bounds.size.height.0 as usize * 3];
875
876 let glyph_analysis = self.create_glyph_run_analysis(params)?;
877 unsafe {
878 glyph_analysis.CreateAlphaTexture(
879 DWRITE_TEXTURE_CLEARTYPE_3x1,
880 &RECT {
881 left: glyph_bounds.origin.x.0,
882 top: glyph_bounds.origin.y.0,
883 right: glyph_bounds.size.width.0 + glyph_bounds.origin.x.0,
884 bottom: glyph_bounds.size.height.0 + glyph_bounds.origin.y.0,
885 },
886 &mut bitmap_data,
887 )?;
888 }
889
890 let bitmap_factory = self.components.bitmap_factory.resolve()?;
891 let bitmap = unsafe {
892 bitmap_factory.CreateBitmapFromMemory(
893 glyph_bounds.size.width.0 as u32,
894 glyph_bounds.size.height.0 as u32,
895 &GUID_WICPixelFormat24bppRGB,
896 glyph_bounds.size.width.0 as u32 * 3,
897 &bitmap_data,
898 )
899 }?;
900
901 let grayscale_bitmap =
902 unsafe { WICConvertBitmapSource(&GUID_WICPixelFormat8bppGray, &bitmap) }?;
903
904 let mut bitmap_data =
905 vec![0u8; glyph_bounds.size.width.0 as usize * glyph_bounds.size.height.0 as usize];
906 unsafe {
907 grayscale_bitmap.CopyPixels(
908 std::ptr::null() as _,
909 glyph_bounds.size.width.0 as u32,
910 &mut bitmap_data,
911 )
912 }?;
913
914 Ok(bitmap_data)
915 }
916
917 fn rasterize_color(
918 &self,
919 params: &RenderGlyphParams,
920 glyph_bounds: Bounds<DevicePixels>,
921 ) -> Result<Vec<u8>> {
922 let bitmap_size = glyph_bounds.size;
923 let subpixel_shift = params
924 .subpixel_variant
925 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
926 let baseline_origin_x = subpixel_shift.x / params.scale_factor;
927 let baseline_origin_y = subpixel_shift.y / params.scale_factor;
928
929 let transform = DWRITE_MATRIX {
930 m11: params.scale_factor,
931 m12: 0.0,
932 m21: 0.0,
933 m22: params.scale_factor,
934 dx: 0.0,
935 dy: 0.0,
936 };
937
938 let font = &self.fonts[params.font_id.0];
939 let glyph_id = [params.glyph_id.0 as u16];
940 let advance = [glyph_bounds.size.width.0 as f32];
941 let offset = [DWRITE_GLYPH_OFFSET {
942 advanceOffset: -glyph_bounds.origin.x.0 as f32 / params.scale_factor,
943 ascenderOffset: glyph_bounds.origin.y.0 as f32 / params.scale_factor,
944 }];
945 let glyph_run = DWRITE_GLYPH_RUN {
946 fontFace: unsafe { std::mem::transmute_copy(&font.font_face) },
947 fontEmSize: params.font_size.0,
948 glyphCount: 1,
949 glyphIndices: glyph_id.as_ptr(),
950 glyphAdvances: advance.as_ptr(),
951 glyphOffsets: offset.as_ptr(),
952 isSideways: BOOL(0),
953 bidiLevel: 0,
954 };
955
956 // todo: support formats other than COLR
957 let color_enumerator = unsafe {
958 self.components.factory.TranslateColorGlyphRun(
959 Vector2::new(baseline_origin_x, baseline_origin_y),
960 &glyph_run,
961 None,
962 DWRITE_GLYPH_IMAGE_FORMATS_COLR,
963 DWRITE_MEASURING_MODE_NATURAL,
964 Some(&transform),
965 0,
966 )
967 }?;
968
969 let mut glyph_layers = Vec::new();
970 loop {
971 let color_run = unsafe { color_enumerator.GetCurrentRun() }?;
972 let color_run = unsafe { &*color_run };
973 let image_format = color_run.glyphImageFormat & !DWRITE_GLYPH_IMAGE_FORMATS_TRUETYPE;
974 if image_format == DWRITE_GLYPH_IMAGE_FORMATS_COLR {
975 let color_analysis = unsafe {
976 self.components.factory.CreateGlyphRunAnalysis(
977 &color_run.Base.glyphRun as *const _,
978 Some(&transform),
979 DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC,
980 DWRITE_MEASURING_MODE_NATURAL,
981 DWRITE_GRID_FIT_MODE_DEFAULT,
982 DWRITE_TEXT_ANTIALIAS_MODE_CLEARTYPE,
983 baseline_origin_x,
984 baseline_origin_y,
985 )
986 }?;
987
988 let color_bounds =
989 unsafe { color_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1) }?;
990
991 let color_size = size(
992 color_bounds.right - color_bounds.left,
993 color_bounds.bottom - color_bounds.top,
994 );
995 if color_size.width > 0 && color_size.height > 0 {
996 let mut alpha_data =
997 vec![0u8; (color_size.width * color_size.height * 3) as usize];
998 unsafe {
999 color_analysis.CreateAlphaTexture(
1000 DWRITE_TEXTURE_CLEARTYPE_3x1,
1001 &color_bounds,
1002 &mut alpha_data,
1003 )
1004 }?;
1005
1006 let run_color = {
1007 let run_color = color_run.Base.runColor;
1008 Rgba {
1009 r: run_color.r,
1010 g: run_color.g,
1011 b: run_color.b,
1012 a: run_color.a,
1013 }
1014 };
1015 let bounds = bounds(point(color_bounds.left, color_bounds.top), color_size);
1016 let alpha_data = alpha_data
1017 .chunks_exact(3)
1018 .flat_map(|chunk| [chunk[0], chunk[1], chunk[2], 255])
1019 .collect::<Vec<_>>();
1020 glyph_layers.push(GlyphLayerTexture::new(
1021 &self.components.gpu_state,
1022 run_color,
1023 bounds,
1024 &alpha_data,
1025 )?);
1026 }
1027 }
1028
1029 let has_next = unsafe { color_enumerator.MoveNext() }
1030 .map(|e| e.as_bool())
1031 .unwrap_or(false);
1032 if !has_next {
1033 break;
1034 }
1035 }
1036
1037 let gpu_state = &self.components.gpu_state;
1038 let params_buffer = {
1039 let desc = D3D11_BUFFER_DESC {
1040 ByteWidth: std::mem::size_of::<GlyphLayerTextureParams>() as u32,
1041 Usage: D3D11_USAGE_DYNAMIC,
1042 BindFlags: D3D11_BIND_CONSTANT_BUFFER.0 as u32,
1043 CPUAccessFlags: D3D11_CPU_ACCESS_WRITE.0 as u32,
1044 MiscFlags: 0,
1045 StructureByteStride: 0,
1046 };
1047
1048 let mut buffer = None;
1049 unsafe {
1050 gpu_state
1051 .device
1052 .CreateBuffer(&desc, None, Some(&mut buffer))
1053 }?;
1054 [buffer]
1055 };
1056
1057 let render_target_texture = {
1058 let mut texture = None;
1059 let desc = D3D11_TEXTURE2D_DESC {
1060 Width: bitmap_size.width.0 as u32,
1061 Height: bitmap_size.height.0 as u32,
1062 MipLevels: 1,
1063 ArraySize: 1,
1064 Format: DXGI_FORMAT_B8G8R8A8_UNORM,
1065 SampleDesc: DXGI_SAMPLE_DESC {
1066 Count: 1,
1067 Quality: 0,
1068 },
1069 Usage: D3D11_USAGE_DEFAULT,
1070 BindFlags: D3D11_BIND_RENDER_TARGET.0 as u32,
1071 CPUAccessFlags: 0,
1072 MiscFlags: 0,
1073 };
1074 unsafe {
1075 gpu_state
1076 .device
1077 .CreateTexture2D(&desc, None, Some(&mut texture))
1078 }?;
1079 texture.unwrap()
1080 };
1081
1082 let render_target_view = {
1083 let desc = D3D11_RENDER_TARGET_VIEW_DESC {
1084 Format: DXGI_FORMAT_B8G8R8A8_UNORM,
1085 ViewDimension: D3D11_RTV_DIMENSION_TEXTURE2D,
1086 Anonymous: D3D11_RENDER_TARGET_VIEW_DESC_0 {
1087 Texture2D: D3D11_TEX2D_RTV { MipSlice: 0 },
1088 },
1089 };
1090 let mut rtv = None;
1091 unsafe {
1092 gpu_state.device.CreateRenderTargetView(
1093 &render_target_texture,
1094 Some(&desc),
1095 Some(&mut rtv),
1096 )
1097 }?;
1098 [rtv]
1099 };
1100
1101 let staging_texture = {
1102 let mut texture = None;
1103 let desc = D3D11_TEXTURE2D_DESC {
1104 Width: bitmap_size.width.0 as u32,
1105 Height: bitmap_size.height.0 as u32,
1106 MipLevels: 1,
1107 ArraySize: 1,
1108 Format: DXGI_FORMAT_B8G8R8A8_UNORM,
1109 SampleDesc: DXGI_SAMPLE_DESC {
1110 Count: 1,
1111 Quality: 0,
1112 },
1113 Usage: D3D11_USAGE_STAGING,
1114 BindFlags: 0,
1115 CPUAccessFlags: D3D11_CPU_ACCESS_READ.0 as u32,
1116 MiscFlags: 0,
1117 };
1118 unsafe {
1119 gpu_state
1120 .device
1121 .CreateTexture2D(&desc, None, Some(&mut texture))
1122 }?;
1123 texture.unwrap()
1124 };
1125
1126 let device_context = &gpu_state.device_context;
1127 unsafe { device_context.IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP) };
1128 unsafe { device_context.VSSetShader(&gpu_state.vertex_shader, None) };
1129 unsafe { device_context.PSSetShader(&gpu_state.pixel_shader, None) };
1130 unsafe { device_context.VSSetConstantBuffers(0, Some(¶ms_buffer)) };
1131 unsafe { device_context.PSSetConstantBuffers(0, Some(¶ms_buffer)) };
1132 unsafe { device_context.OMSetRenderTargets(Some(&render_target_view), None) };
1133 unsafe { device_context.PSSetSamplers(0, Some(&gpu_state.sampler)) };
1134 unsafe { device_context.OMSetBlendState(&gpu_state.blend_state, None, 0xffffffff) };
1135
1136 for layer in glyph_layers {
1137 let params = GlyphLayerTextureParams {
1138 run_color: layer.run_color,
1139 bounds: layer.bounds,
1140 };
1141 unsafe {
1142 let mut dest = std::mem::zeroed();
1143 gpu_state.device_context.Map(
1144 params_buffer[0].as_ref().unwrap(),
1145 0,
1146 D3D11_MAP_WRITE_DISCARD,
1147 0,
1148 Some(&mut dest),
1149 )?;
1150 std::ptr::copy_nonoverlapping(¶ms as *const _, dest.pData as *mut _, 1);
1151 gpu_state
1152 .device_context
1153 .Unmap(params_buffer[0].as_ref().unwrap(), 0);
1154 };
1155
1156 let texture = [Some(layer.texture_view)];
1157 unsafe { device_context.PSSetShaderResources(0, Some(&texture)) };
1158
1159 let viewport = [D3D11_VIEWPORT {
1160 TopLeftX: layer.bounds.origin.x as f32,
1161 TopLeftY: layer.bounds.origin.y as f32,
1162 Width: layer.bounds.size.width as f32,
1163 Height: layer.bounds.size.height as f32,
1164 MinDepth: 0.0,
1165 MaxDepth: 1.0,
1166 }];
1167 unsafe { device_context.RSSetViewports(Some(&viewport)) };
1168
1169 unsafe { device_context.Draw(4, 0) };
1170 }
1171
1172 unsafe { device_context.CopyResource(&staging_texture, &render_target_texture) };
1173
1174 let mapped_data = {
1175 let mut mapped_data = D3D11_MAPPED_SUBRESOURCE::default();
1176 unsafe {
1177 device_context.Map(
1178 &staging_texture,
1179 0,
1180 D3D11_MAP_READ,
1181 0,
1182 Some(&mut mapped_data),
1183 )
1184 }?;
1185 mapped_data
1186 };
1187 let mut rasterized =
1188 vec![0u8; (bitmap_size.width.0 as u32 * bitmap_size.height.0 as u32 * 4) as usize];
1189
1190 for y in 0..bitmap_size.height.0 as usize {
1191 let width = bitmap_size.width.0 as usize;
1192 unsafe {
1193 std::ptr::copy_nonoverlapping::<u8>(
1194 (mapped_data.pData as *const u8).byte_add(mapped_data.RowPitch as usize * y),
1195 rasterized
1196 .as_mut_ptr()
1197 .byte_add(width * y * std::mem::size_of::<u32>()),
1198 width * std::mem::size_of::<u32>(),
1199 )
1200 };
1201 }
1202
1203 Ok(rasterized)
1204 }
1205
1206 fn get_typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
1207 unsafe {
1208 let font = &self.fonts[font_id.0].font_face;
1209 let glyph_indices = [glyph_id.0 as u16];
1210 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
1211 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
1212
1213 let metrics = &metrics[0];
1214 let advance_width = metrics.advanceWidth as i32;
1215 let advance_height = metrics.advanceHeight as i32;
1216 let left_side_bearing = metrics.leftSideBearing;
1217 let right_side_bearing = metrics.rightSideBearing;
1218 let top_side_bearing = metrics.topSideBearing;
1219 let bottom_side_bearing = metrics.bottomSideBearing;
1220 let vertical_origin_y = metrics.verticalOriginY;
1221
1222 let y_offset = vertical_origin_y + bottom_side_bearing - advance_height;
1223 let width = advance_width - (left_side_bearing + right_side_bearing);
1224 let height = advance_height - (top_side_bearing + bottom_side_bearing);
1225
1226 Ok(Bounds {
1227 origin: Point {
1228 x: left_side_bearing as f32,
1229 y: y_offset as f32,
1230 },
1231 size: Size {
1232 width: width as f32,
1233 height: height as f32,
1234 },
1235 })
1236 }
1237 }
1238
1239 fn get_advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
1240 unsafe {
1241 let font = &self.fonts[font_id.0].font_face;
1242 let glyph_indices = [glyph_id.0 as u16];
1243 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
1244 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
1245
1246 let metrics = &metrics[0];
1247
1248 Ok(Size {
1249 width: metrics.advanceWidth as f32,
1250 height: 0.0,
1251 })
1252 }
1253 }
1254
1255 fn all_font_names(&self) -> Vec<String> {
1256 let mut result =
1257 get_font_names_from_collection(&self.system_font_collection, &self.components.locale);
1258 result.extend(get_font_names_from_collection(
1259 &self.custom_font_collection,
1260 &self.components.locale,
1261 ));
1262 result
1263 }
1264}
1265
1266impl Drop for DirectWriteState {
1267 fn drop(&mut self) {
1268 unsafe {
1269 let _ = self
1270 .components
1271 .factory
1272 .UnregisterFontFileLoader(&self.components.in_memory_loader);
1273 }
1274 }
1275}
1276
1277struct GlyphLayerTexture {
1278 run_color: Rgba,
1279 bounds: Bounds<i32>,
1280 texture: ID3D11Texture2D,
1281 texture_view: ID3D11ShaderResourceView,
1282}
1283
1284impl GlyphLayerTexture {
1285 pub fn new(
1286 gpu_state: &GPUState,
1287 run_color: Rgba,
1288 bounds: Bounds<i32>,
1289 alpha_data: &[u8],
1290 ) -> Result<Self> {
1291 let texture_size = bounds.size;
1292
1293 let desc = D3D11_TEXTURE2D_DESC {
1294 Width: texture_size.width as u32,
1295 Height: texture_size.height as u32,
1296 MipLevels: 1,
1297 ArraySize: 1,
1298 Format: DXGI_FORMAT_R8G8B8A8_UNORM,
1299 SampleDesc: DXGI_SAMPLE_DESC {
1300 Count: 1,
1301 Quality: 0,
1302 },
1303 Usage: D3D11_USAGE_DEFAULT,
1304 BindFlags: D3D11_BIND_SHADER_RESOURCE.0 as u32,
1305 CPUAccessFlags: D3D11_CPU_ACCESS_WRITE.0 as u32,
1306 MiscFlags: 0,
1307 };
1308
1309 let texture = {
1310 let mut texture: Option<ID3D11Texture2D> = None;
1311 unsafe {
1312 gpu_state
1313 .device
1314 .CreateTexture2D(&desc, None, Some(&mut texture))?
1315 };
1316 texture.unwrap()
1317 };
1318 let texture_view = {
1319 let mut view: Option<ID3D11ShaderResourceView> = None;
1320 unsafe {
1321 gpu_state
1322 .device
1323 .CreateShaderResourceView(&texture, None, Some(&mut view))?
1324 };
1325 view.unwrap()
1326 };
1327
1328 unsafe {
1329 gpu_state.device_context.UpdateSubresource(
1330 &texture,
1331 0,
1332 None,
1333 alpha_data.as_ptr() as _,
1334 (texture_size.width * 4) as u32,
1335 0,
1336 )
1337 };
1338
1339 Ok(GlyphLayerTexture {
1340 run_color,
1341 bounds,
1342 texture,
1343 texture_view,
1344 })
1345 }
1346}
1347
1348#[repr(C)]
1349struct GlyphLayerTextureParams {
1350 bounds: Bounds<i32>,
1351 run_color: Rgba,
1352}
1353
1354struct TextRendererWrapper(pub IDWriteTextRenderer);
1355
1356impl TextRendererWrapper {
1357 pub fn new(locale_str: &str) -> Self {
1358 let inner = TextRenderer::new(locale_str);
1359 TextRendererWrapper(inner.into())
1360 }
1361}
1362
1363#[implement(IDWriteTextRenderer)]
1364struct TextRenderer {
1365 locale: String,
1366}
1367
1368impl TextRenderer {
1369 pub fn new(locale_str: &str) -> Self {
1370 TextRenderer {
1371 locale: locale_str.to_owned(),
1372 }
1373 }
1374}
1375
1376struct RendererContext<'t, 'a, 'b> {
1377 text_system: &'t mut DirectWriteState,
1378 index_converter: StringIndexConverter<'a>,
1379 runs: &'b mut Vec<ShapedRun>,
1380 width: f32,
1381}
1382
1383#[derive(Debug)]
1384struct ClusterAnalyzer<'t> {
1385 utf16_idx: usize,
1386 glyph_idx: usize,
1387 glyph_count: usize,
1388 cluster_map: &'t [u16],
1389}
1390
1391impl<'t> ClusterAnalyzer<'t> {
1392 pub fn new(cluster_map: &'t [u16], glyph_count: usize) -> Self {
1393 ClusterAnalyzer {
1394 utf16_idx: 0,
1395 glyph_idx: 0,
1396 glyph_count,
1397 cluster_map,
1398 }
1399 }
1400}
1401
1402impl Iterator for ClusterAnalyzer<'_> {
1403 type Item = (usize, usize);
1404
1405 fn next(&mut self) -> Option<(usize, usize)> {
1406 if self.utf16_idx >= self.cluster_map.len() {
1407 return None; // No more clusters
1408 }
1409 let start_utf16_idx = self.utf16_idx;
1410 let current_glyph = self.cluster_map[start_utf16_idx] as usize;
1411
1412 // Find the end of current cluster (where glyph index changes)
1413 let mut end_utf16_idx = start_utf16_idx + 1;
1414 while end_utf16_idx < self.cluster_map.len()
1415 && self.cluster_map[end_utf16_idx] as usize == current_glyph
1416 {
1417 end_utf16_idx += 1;
1418 }
1419
1420 let utf16_len = end_utf16_idx - start_utf16_idx;
1421
1422 // Calculate glyph count for this cluster
1423 let next_glyph = if end_utf16_idx < self.cluster_map.len() {
1424 self.cluster_map[end_utf16_idx] as usize
1425 } else {
1426 self.glyph_count
1427 };
1428
1429 let glyph_count = next_glyph - current_glyph;
1430
1431 // Update state for next call
1432 self.utf16_idx = end_utf16_idx;
1433 self.glyph_idx = next_glyph;
1434
1435 Some((utf16_len, glyph_count))
1436 }
1437}
1438
1439#[allow(non_snake_case)]
1440impl IDWritePixelSnapping_Impl for TextRenderer_Impl {
1441 fn IsPixelSnappingDisabled(
1442 &self,
1443 _clientdrawingcontext: *const ::core::ffi::c_void,
1444 ) -> windows::core::Result<BOOL> {
1445 Ok(BOOL(0))
1446 }
1447
1448 fn GetCurrentTransform(
1449 &self,
1450 _clientdrawingcontext: *const ::core::ffi::c_void,
1451 transform: *mut DWRITE_MATRIX,
1452 ) -> windows::core::Result<()> {
1453 unsafe {
1454 *transform = DWRITE_MATRIX {
1455 m11: 1.0,
1456 m12: 0.0,
1457 m21: 0.0,
1458 m22: 1.0,
1459 dx: 0.0,
1460 dy: 0.0,
1461 };
1462 }
1463 Ok(())
1464 }
1465
1466 fn GetPixelsPerDip(
1467 &self,
1468 _clientdrawingcontext: *const ::core::ffi::c_void,
1469 ) -> windows::core::Result<f32> {
1470 Ok(1.0)
1471 }
1472}
1473
1474#[allow(non_snake_case)]
1475impl IDWriteTextRenderer_Impl for TextRenderer_Impl {
1476 fn DrawGlyphRun(
1477 &self,
1478 clientdrawingcontext: *const ::core::ffi::c_void,
1479 _baselineoriginx: f32,
1480 _baselineoriginy: f32,
1481 _measuringmode: DWRITE_MEASURING_MODE,
1482 glyphrun: *const DWRITE_GLYPH_RUN,
1483 glyphrundescription: *const DWRITE_GLYPH_RUN_DESCRIPTION,
1484 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1485 ) -> windows::core::Result<()> {
1486 let glyphrun = unsafe { &*glyphrun };
1487 let glyph_count = glyphrun.glyphCount as usize;
1488 if glyph_count == 0 || glyphrun.fontFace.is_none() {
1489 return Ok(());
1490 }
1491 let desc = unsafe { &*glyphrundescription };
1492 let context = unsafe {
1493 &mut *(clientdrawingcontext as *const RendererContext as *mut RendererContext)
1494 };
1495 let font_face = glyphrun.fontFace.as_ref().unwrap();
1496 // This `cast()` action here should never fail since we are running on Win10+, and
1497 // `IDWriteFontFace3` requires Win10
1498 let font_face = &font_face.cast::<IDWriteFontFace3>().unwrap();
1499 let Some((font_identifier, font_struct, color_font)) =
1500 get_font_identifier_and_font_struct(font_face, &self.locale)
1501 else {
1502 return Ok(());
1503 };
1504
1505 let font_id = if let Some(id) = context
1506 .text_system
1507 .font_id_by_identifier
1508 .get(&font_identifier)
1509 {
1510 *id
1511 } else {
1512 context.text_system.select_font(&font_struct)
1513 };
1514
1515 let glyph_ids = unsafe { std::slice::from_raw_parts(glyphrun.glyphIndices, glyph_count) };
1516 let glyph_advances =
1517 unsafe { std::slice::from_raw_parts(glyphrun.glyphAdvances, glyph_count) };
1518 let glyph_offsets =
1519 unsafe { std::slice::from_raw_parts(glyphrun.glyphOffsets, glyph_count) };
1520 let cluster_map =
1521 unsafe { std::slice::from_raw_parts(desc.clusterMap, desc.stringLength as usize) };
1522
1523 let mut cluster_analyzer = ClusterAnalyzer::new(cluster_map, glyph_count);
1524 let mut utf16_idx = desc.textPosition as usize;
1525 let mut glyph_idx = 0;
1526 let mut glyphs = Vec::with_capacity(glyph_count);
1527 for (cluster_utf16_len, cluster_glyph_count) in cluster_analyzer {
1528 context.index_converter.advance_to_utf16_ix(utf16_idx);
1529 utf16_idx += cluster_utf16_len;
1530 for (cluster_glyph_idx, glyph_id) in glyph_ids
1531 [glyph_idx..(glyph_idx + cluster_glyph_count)]
1532 .iter()
1533 .enumerate()
1534 {
1535 let id = GlyphId(*glyph_id as u32);
1536 let is_emoji = color_font
1537 && is_color_glyph(font_face, id, &context.text_system.components.factory);
1538 let this_glyph_idx = glyph_idx + cluster_glyph_idx;
1539 glyphs.push(ShapedGlyph {
1540 id,
1541 position: point(
1542 px(context.width + glyph_offsets[this_glyph_idx].advanceOffset),
1543 px(0.0),
1544 ),
1545 index: context.index_converter.utf8_ix,
1546 is_emoji,
1547 });
1548 context.width += glyph_advances[this_glyph_idx];
1549 }
1550 glyph_idx += cluster_glyph_count;
1551 }
1552 context.runs.push(ShapedRun { font_id, glyphs });
1553 Ok(())
1554 }
1555
1556 fn DrawUnderline(
1557 &self,
1558 _clientdrawingcontext: *const ::core::ffi::c_void,
1559 _baselineoriginx: f32,
1560 _baselineoriginy: f32,
1561 _underline: *const DWRITE_UNDERLINE,
1562 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1563 ) -> windows::core::Result<()> {
1564 Err(windows::core::Error::new(
1565 E_NOTIMPL,
1566 "DrawUnderline unimplemented",
1567 ))
1568 }
1569
1570 fn DrawStrikethrough(
1571 &self,
1572 _clientdrawingcontext: *const ::core::ffi::c_void,
1573 _baselineoriginx: f32,
1574 _baselineoriginy: f32,
1575 _strikethrough: *const DWRITE_STRIKETHROUGH,
1576 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1577 ) -> windows::core::Result<()> {
1578 Err(windows::core::Error::new(
1579 E_NOTIMPL,
1580 "DrawStrikethrough unimplemented",
1581 ))
1582 }
1583
1584 fn DrawInlineObject(
1585 &self,
1586 _clientdrawingcontext: *const ::core::ffi::c_void,
1587 _originx: f32,
1588 _originy: f32,
1589 _inlineobject: windows::core::Ref<IDWriteInlineObject>,
1590 _issideways: BOOL,
1591 _isrighttoleft: BOOL,
1592 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1593 ) -> windows::core::Result<()> {
1594 Err(windows::core::Error::new(
1595 E_NOTIMPL,
1596 "DrawInlineObject unimplemented",
1597 ))
1598 }
1599}
1600
1601struct StringIndexConverter<'a> {
1602 text: &'a str,
1603 utf8_ix: usize,
1604 utf16_ix: usize,
1605}
1606
1607impl<'a> StringIndexConverter<'a> {
1608 fn new(text: &'a str) -> Self {
1609 Self {
1610 text,
1611 utf8_ix: 0,
1612 utf16_ix: 0,
1613 }
1614 }
1615
1616 #[allow(dead_code)]
1617 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
1618 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1619 if self.utf8_ix + ix >= utf8_target {
1620 self.utf8_ix += ix;
1621 return;
1622 }
1623 self.utf16_ix += c.len_utf16();
1624 }
1625 self.utf8_ix = self.text.len();
1626 }
1627
1628 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
1629 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1630 if self.utf16_ix >= utf16_target {
1631 self.utf8_ix += ix;
1632 return;
1633 }
1634 self.utf16_ix += c.len_utf16();
1635 }
1636 self.utf8_ix = self.text.len();
1637 }
1638}
1639
1640impl Into<DWRITE_FONT_STYLE> for FontStyle {
1641 fn into(self) -> DWRITE_FONT_STYLE {
1642 match self {
1643 FontStyle::Normal => DWRITE_FONT_STYLE_NORMAL,
1644 FontStyle::Italic => DWRITE_FONT_STYLE_ITALIC,
1645 FontStyle::Oblique => DWRITE_FONT_STYLE_OBLIQUE,
1646 }
1647 }
1648}
1649
1650impl From<DWRITE_FONT_STYLE> for FontStyle {
1651 fn from(value: DWRITE_FONT_STYLE) -> Self {
1652 match value.0 {
1653 0 => FontStyle::Normal,
1654 1 => FontStyle::Italic,
1655 2 => FontStyle::Oblique,
1656 _ => unreachable!(),
1657 }
1658 }
1659}
1660
1661impl Into<DWRITE_FONT_WEIGHT> for FontWeight {
1662 fn into(self) -> DWRITE_FONT_WEIGHT {
1663 DWRITE_FONT_WEIGHT(self.0 as i32)
1664 }
1665}
1666
1667impl From<DWRITE_FONT_WEIGHT> for FontWeight {
1668 fn from(value: DWRITE_FONT_WEIGHT) -> Self {
1669 FontWeight(value.0 as f32)
1670 }
1671}
1672
1673fn get_font_names_from_collection(
1674 collection: &IDWriteFontCollection1,
1675 locale: &str,
1676) -> Vec<String> {
1677 unsafe {
1678 let mut result = Vec::new();
1679 let family_count = collection.GetFontFamilyCount();
1680 for index in 0..family_count {
1681 let Some(font_family) = collection.GetFontFamily(index).log_err() else {
1682 continue;
1683 };
1684 let Some(localized_family_name) = font_family.GetFamilyNames().log_err() else {
1685 continue;
1686 };
1687 let Some(family_name) = get_name(localized_family_name, locale).log_err() else {
1688 continue;
1689 };
1690 result.push(family_name);
1691 }
1692
1693 result
1694 }
1695}
1696
1697fn get_font_identifier_and_font_struct(
1698 font_face: &IDWriteFontFace3,
1699 locale: &str,
1700) -> Option<(FontIdentifier, Font, bool)> {
1701 let postscript_name = get_postscript_name(font_face, locale).log_err()?;
1702 let localized_family_name = unsafe { font_face.GetFamilyNames().log_err() }?;
1703 let family_name = get_name(localized_family_name, locale).log_err()?;
1704 let weight = unsafe { font_face.GetWeight() };
1705 let style = unsafe { font_face.GetStyle() };
1706 let identifier = FontIdentifier {
1707 postscript_name,
1708 weight: weight.0,
1709 style: style.0,
1710 };
1711 let font_struct = Font {
1712 family: family_name.into(),
1713 features: FontFeatures::default(),
1714 weight: weight.into(),
1715 style: style.into(),
1716 fallbacks: None,
1717 };
1718 let is_emoji = unsafe { font_face.IsColorFont().as_bool() };
1719 Some((identifier, font_struct, is_emoji))
1720}
1721
1722#[inline]
1723fn get_font_identifier(font_face: &IDWriteFontFace3, locale: &str) -> Option<FontIdentifier> {
1724 let weight = unsafe { font_face.GetWeight().0 };
1725 let style = unsafe { font_face.GetStyle().0 };
1726 get_postscript_name(font_face, locale)
1727 .log_err()
1728 .map(|postscript_name| FontIdentifier {
1729 postscript_name,
1730 weight,
1731 style,
1732 })
1733}
1734
1735#[inline]
1736fn get_postscript_name(font_face: &IDWriteFontFace3, locale: &str) -> Result<String> {
1737 let mut info = None;
1738 let mut exists = BOOL(0);
1739 unsafe {
1740 font_face.GetInformationalStrings(
1741 DWRITE_INFORMATIONAL_STRING_POSTSCRIPT_NAME,
1742 &mut info,
1743 &mut exists,
1744 )?
1745 };
1746 if !exists.as_bool() || info.is_none() {
1747 anyhow::bail!("No postscript name found for font face");
1748 }
1749
1750 get_name(info.unwrap(), locale)
1751}
1752
1753// https://learn.microsoft.com/en-us/windows/win32/api/dwrite/ne-dwrite-dwrite_font_feature_tag
1754fn apply_font_features(
1755 direct_write_features: &IDWriteTypography,
1756 features: &FontFeatures,
1757) -> Result<()> {
1758 let tag_values = features.tag_value_list();
1759 if tag_values.is_empty() {
1760 return Ok(());
1761 }
1762
1763 // All of these features are enabled by default by DirectWrite.
1764 // If you want to (and can) peek into the source of DirectWrite
1765 let mut feature_liga = make_direct_write_feature("liga", 1);
1766 let mut feature_clig = make_direct_write_feature("clig", 1);
1767 let mut feature_calt = make_direct_write_feature("calt", 1);
1768
1769 for (tag, value) in tag_values {
1770 if tag.as_str() == "liga" && *value == 0 {
1771 feature_liga.parameter = 0;
1772 continue;
1773 }
1774 if tag.as_str() == "clig" && *value == 0 {
1775 feature_clig.parameter = 0;
1776 continue;
1777 }
1778 if tag.as_str() == "calt" && *value == 0 {
1779 feature_calt.parameter = 0;
1780 continue;
1781 }
1782
1783 unsafe {
1784 direct_write_features.AddFontFeature(make_direct_write_feature(&tag, *value))?;
1785 }
1786 }
1787 unsafe {
1788 direct_write_features.AddFontFeature(feature_liga)?;
1789 direct_write_features.AddFontFeature(feature_clig)?;
1790 direct_write_features.AddFontFeature(feature_calt)?;
1791 }
1792
1793 Ok(())
1794}
1795
1796#[inline]
1797const fn make_direct_write_feature(feature_name: &str, parameter: u32) -> DWRITE_FONT_FEATURE {
1798 let tag = make_direct_write_tag(feature_name);
1799 DWRITE_FONT_FEATURE {
1800 nameTag: tag,
1801 parameter,
1802 }
1803}
1804
1805#[inline]
1806const fn make_open_type_tag(tag_name: &str) -> u32 {
1807 let bytes = tag_name.as_bytes();
1808 debug_assert!(bytes.len() == 4);
1809 u32::from_le_bytes([bytes[0], bytes[1], bytes[2], bytes[3]])
1810}
1811
1812#[inline]
1813const fn make_direct_write_tag(tag_name: &str) -> DWRITE_FONT_FEATURE_TAG {
1814 DWRITE_FONT_FEATURE_TAG(make_open_type_tag(tag_name))
1815}
1816
1817#[inline]
1818fn get_name(string: IDWriteLocalizedStrings, locale: &str) -> Result<String> {
1819 let mut locale_name_index = 0u32;
1820 let mut exists = BOOL(0);
1821 unsafe {
1822 string.FindLocaleName(
1823 &HSTRING::from(locale),
1824 &mut locale_name_index,
1825 &mut exists as _,
1826 )?
1827 };
1828 if !exists.as_bool() {
1829 unsafe {
1830 string.FindLocaleName(
1831 DEFAULT_LOCALE_NAME,
1832 &mut locale_name_index as _,
1833 &mut exists as _,
1834 )?
1835 };
1836 anyhow::ensure!(exists.as_bool(), "No localised string for {locale}");
1837 }
1838
1839 let name_length = unsafe { string.GetStringLength(locale_name_index) }? as usize;
1840 let mut name_vec = vec![0u16; name_length + 1];
1841 unsafe {
1842 string.GetString(locale_name_index, &mut name_vec)?;
1843 }
1844
1845 Ok(String::from_utf16_lossy(&name_vec[..name_length]))
1846}
1847
1848fn get_system_ui_font_name() -> SharedString {
1849 unsafe {
1850 let mut info: LOGFONTW = std::mem::zeroed();
1851 let font_family = if SystemParametersInfoW(
1852 SPI_GETICONTITLELOGFONT,
1853 std::mem::size_of::<LOGFONTW>() as u32,
1854 Some(&mut info as *mut _ as _),
1855 SYSTEM_PARAMETERS_INFO_UPDATE_FLAGS(0),
1856 )
1857 .log_err()
1858 .is_none()
1859 {
1860 // https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts
1861 // Segoe UI is the Windows font intended for user interface text strings.
1862 "Segoe UI".into()
1863 } else {
1864 let font_name = String::from_utf16_lossy(&info.lfFaceName);
1865 font_name.trim_matches(char::from(0)).to_owned().into()
1866 };
1867 log::info!("Use {} as UI font.", font_family);
1868 font_family
1869 }
1870}
1871
1872// One would think that with newer DirectWrite method: IDWriteFontFace4::GetGlyphImageFormats
1873// but that doesn't seem to work for some glyphs, say ❤
1874fn is_color_glyph(
1875 font_face: &IDWriteFontFace3,
1876 glyph_id: GlyphId,
1877 factory: &IDWriteFactory5,
1878) -> bool {
1879 let glyph_run = DWRITE_GLYPH_RUN {
1880 fontFace: unsafe { std::mem::transmute_copy(font_face) },
1881 fontEmSize: 14.0,
1882 glyphCount: 1,
1883 glyphIndices: &(glyph_id.0 as u16),
1884 glyphAdvances: &0.0,
1885 glyphOffsets: &DWRITE_GLYPH_OFFSET {
1886 advanceOffset: 0.0,
1887 ascenderOffset: 0.0,
1888 },
1889 isSideways: BOOL(0),
1890 bidiLevel: 0,
1891 };
1892 unsafe {
1893 factory.TranslateColorGlyphRun(
1894 Vector2::default(),
1895 &glyph_run as _,
1896 None,
1897 DWRITE_GLYPH_IMAGE_FORMATS_COLR
1898 | DWRITE_GLYPH_IMAGE_FORMATS_SVG
1899 | DWRITE_GLYPH_IMAGE_FORMATS_PNG
1900 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
1901 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8,
1902 DWRITE_MEASURING_MODE_NATURAL,
1903 None,
1904 0,
1905 )
1906 }
1907 .is_ok()
1908}
1909
1910const DEFAULT_LOCALE_NAME: PCWSTR = windows::core::w!("en-US");
1911
1912#[cfg(test)]
1913mod tests {
1914 use crate::platform::windows::direct_write::ClusterAnalyzer;
1915
1916 #[test]
1917 fn test_cluster_map() {
1918 let cluster_map = [0];
1919 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 1);
1920 let next = analyzer.next();
1921 assert_eq!(next, Some((1, 1)));
1922 let next = analyzer.next();
1923 assert_eq!(next, None);
1924
1925 let cluster_map = [0, 1, 2];
1926 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 3);
1927 let next = analyzer.next();
1928 assert_eq!(next, Some((1, 1)));
1929 let next = analyzer.next();
1930 assert_eq!(next, Some((1, 1)));
1931 let next = analyzer.next();
1932 assert_eq!(next, Some((1, 1)));
1933 let next = analyzer.next();
1934 assert_eq!(next, None);
1935 // 👨👩👧👦👩💻
1936 let cluster_map = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 4, 4, 4];
1937 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 5);
1938 let next = analyzer.next();
1939 assert_eq!(next, Some((11, 4)));
1940 let next = analyzer.next();
1941 assert_eq!(next, Some((5, 1)));
1942 let next = analyzer.next();
1943 assert_eq!(next, None);
1944 // 👩💻
1945 let cluster_map = [0, 0, 0, 0, 0];
1946 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 1);
1947 let next = analyzer.next();
1948 assert_eq!(next, Some((5, 1)));
1949 let next = analyzer.next();
1950 assert_eq!(next, None);
1951 }
1952}